The Study of the Parameters that Affect the Performance of Suspension in HDD
Issue:
Volume 4, Issue 2, June 2019
Pages:
17-23
Received:
10 June 2019
Accepted:
10 July 2019
Published:
26 July 2019
Abstract: The suspension in a hard disk drive is a component of hard disk drives (HDD(s)) that commonly consist of three main components; Baseplate, Loadbeam and Gimbal, which are welded together. The suspension is attached to a slider fly on the surface of a rapidly spinning disk. The suspension assembly and slider that is formed is called a Head Gimbal Assembly (HGA). If that assembly is not attached to the slider, that is called a Trace Gimbal Assembly (TSA). Defects in the suspension may occur from machining and assembly. The aim of this research is to study the effect of suspension defects on the performance of the suspension resonance using a finite element method, whereby the suspension was created by SolidWorks and imported into Ansys in order to conduct resonance analysis. The results from finite element analysis compared with laser doppler velocimetry (LDV) found that the trend is the same. The suspension bias was revealed, in that Delta RG, welding diameter, program asymmetry, program asymmetry, tip height and tip twist influence the performance of the suspension may possibly come from the suspension production process. Obviously, this process needs to be controlled with regard to certain aspects, such as laser power, fixtures and so on. However, the swaging process in the head stack assembly might also have an impact tin tip height and tip twist.
Abstract: The suspension in a hard disk drive is a component of hard disk drives (HDD(s)) that commonly consist of three main components; Baseplate, Loadbeam and Gimbal, which are welded together. The suspension is attached to a slider fly on the surface of a rapidly spinning disk. The suspension assembly and slider that is formed is called a Head Gimbal Ass...
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Complex Dynamics of the Chua’s Circuit System with Adjustable Symmetry and Nonlinearity: Multistability and Simple Circuit Realization
Nestor Tsafack,
Jacques Kengne
Issue:
Volume 4, Issue 2, June 2019
Pages:
24-34
Received:
25 July 2019
Accepted:
13 August 2019
Published:
11 September 2019
Abstract: Background: Since the invention of Chua’s circuit, numerous generalizations based on substitution of the nonlinear function have been reported. One of the generalizations is obtained by replacing the piecewise-linear with the cubic and/or quadratic polynomial. These nonlinearities are used to be implement using analog multipliers which are relatively expensive. In this realization we propose a different approach to synthetize both cubic and quadratic nonlinearities of empirical Chua’s circuit. Methods: The idea is to use diodes, Opamps and resistors to derive a PWL approximation of the cubic and quadratic functions. To demonstrate some complex phenomena observed in the system using the fourth order Runge-Kutta numerical integration method with a very small integration step. The bifurcation diagram which is the plot of local maxima of the temporal trace of a system’s coordinate as a function of the control parameter also constitutes an excellent tool for the study of dynamic systems. Results: The above mentioned standard nonlinear analysis tools have been exploited and it is found that the system with adjustable symmetry experiences a plethora of symmetric and asymmetric coexisting attractors. A particular feature of the system is related to the simplicity of the corresponding electronic analog circuit (no analog multiplier chip used to implement the cubic and quadratic nonlinearities). Conclusions: It is observed that the proposed Chua’s circuit system is more flexible (both symmetric and asymmetric) and displays complex dynamics behaviors of symmetric and asymmetric coexisting attractors. Note that this striking dynamic can be exploited in encryption algorithms.
Abstract: Background: Since the invention of Chua’s circuit, numerous generalizations based on substitution of the nonlinear function have been reported. One of the generalizations is obtained by replacing the piecewise-linear with the cubic and/or quadratic polynomial. These nonlinearities are used to be implement using analog multipliers which are relative...
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